Hydraulic cylinder with end cover anti-retreating function

Abstract

The hydraulic cylinder comprises a cylinder barrel, a front end cover, a rear end cover and a pair of flanges, the front end cover is in threaded connection with the inner wall of the front end of the cylinder barrel, the rear end cover is in threaded connection with the inner wall of the rear end of the cylinder barrel, and the pair of flanges is in threaded connection with the two ends of the outer side wall of the cylinder barrel respectively. The front end cover and the rear end cover are respectively connected with one of the flanges through bolts; the cylinder barrel, the front end cover, the rear end cover and the pair of flanges form a self-locking mechanism. According to the hydraulic cylinder with the end cover anti-retreating function, the phenomenon that the end cover of the hydraulic cylinder loosens and retreats due to vibration can be prevented through the structure of the hydraulic cylinder.

Description

Technical Field

[0001] The utility model relates to the field of hydraulic cylinders, in particular to a hydraulic cylinder with an end cover anti-retraction function. Background Art

[0002] As an important driving component, hydraulic cylinders are widely used in various equipment. However, since the equipment usually has a certain amount of vibration during operation, the vibration will be transmitted to the hydraulic cylinder, causing the cylinder end cover on the hydraulic cylinder to loosen or even the end cover to withdraw. In order to overcome the above defects, hydraulic cylinders usually use structures such as tightening screws, welding, and pit structures as end cover anti-loosening structures. However, due to the influence of the use environment, hydraulic cylinders are usually in a high temperature, high humidity, and high corrosion environment for a long time. The seals are prone to aging and the internal leakage control requirements of the cylinder are relatively strict. Therefore, after the seal of this type of cylinder ages, it is necessary to disassemble and replace the seal in time. However, when tightening screws, welding structures, and pit structures are used as end cover anti-loosening structures, problems such as cylinder deformation and end face damage will occur after multiple disassembly.

[0003] The utility model patent with the authorization announcement number CN204127032U discloses a hydraulic cylinder anti-leakage oil end cover, which has a through hole penetrating the end cover, and the end cover has an oil collecting groove, which is formed on the inner wall surface of the through hole, and the extension direction of the oil collecting groove has an angle with the axial direction of the through hole, and the angle is greater than 0 degrees and less than 180 degrees. During use, when the hydraulic cylinder leaks oil, especially when the sealing ring is damaged, the oil will not overflow to the outside of the hydraulic cylinder, but will flow into the oil collecting groove, and the hydraulic cylinder can continue to work, and then find a suitable time for maintenance and replacement of the sealing ring, thereby improving work efficiency. Although the hydraulic cylinder anti-leakage oil end cover can meet the requirements for internal leakage control of the oil cylinder, it does not solve the problem of loosening and withdrawal of the hydraulic cylinder end cover due to vibration. Utility Model Content

[0004] In order to utilize the structure of the hydraulic cylinder itself to prevent the hydraulic cylinder end cover from loosening and retreating due to vibration, the technical solution adopted by the utility model is: a hydraulic cylinder with an end cover anti-retreat function, comprising a cylinder barrel, a front end cover, a rear end cover and a pair of flanges, the front end cover is threadedly connected to the inner wall of the front end of the cylinder barrel, the rear end cover is threadedly connected to the inner wall of the rear end of the cylinder barrel, and the pair of flanges are respectively threadedly connected to the two ends of the outer side wall of the cylinder barrel; the front end cover and the rear end cover are respectively bolted to one of the flanges;

[0005] The cylinder barrel, the front end cover, the rear end cover and a pair of flanges form a self-locking mechanism.

[0006] Based on the above, in order to facilitate the removal of the front cover and the rear cover from the cylinder, the outer walls of the cylinder are provided with external cylinder threads at both ends, and the inner walls of the cylinder are provided with internal cylinder threads at both ends, and the pitch value of the external cylinder threads is different from the pitch value of the internal cylinder threads.

[0007] Based on the above, in order to facilitate processing and installation, the step of distinguishing the front end and the rear end of the cylinder is omitted, and the pitch values ​​of the external threads of the cylinder located at both ends of the cylinder are the same.

[0008] Based on the above, in order to facilitate processing and installation, the step of distinguishing the front end and the rear end of the cylinder is omitted, and the pitch values ​​of the internal threads of the cylinder located at both ends of the cylinder are the same.

[0009] Based on the above, in order to cooperate with the cylinder barrel, the inner end of the front end cover is provided with a front end cover external thread, and the inner end of the rear end cover is provided with a rear end cover external thread, and the pitch value of the front end cover external thread is the same as the pitch value of the rear end cover external thread.

[0010] Based on the above, in order to connect the front cover and the rear cover to the cylinder barrel through bolts, the flange has a circular array of multiple threaded holes, and the front cover and the rear cover are respectively provided with multiple bolt holes, and the bolt holes are arranged corresponding to the threaded holes.

[0011] Based on the above, in order to improve the sealing performance of the hydraulic cylinder, a front end cover sealing surface is provided at the inner end of the front end cover, and a rear end cover sealing surface is provided at the inner end of the rear end cover. Sealing rings are respectively provided on the front end cover sealing surface and the rear end cover sealing surface, and sealing ring grooves are respectively provided on the inner side wall of the cylinder barrel corresponding to the sealing rings.

[0012] Based on the above, a piston rod is also slidably arranged in the cylinder, a piston is installed at the bottom end of the piston rod, the top end of the piston rod extends out of the front end cover, and seals are respectively arranged between the piston rod and the front end cover and on the piston.

[0013] Based on the above, in order to facilitate lubrication inside the cylinder, liquid holes are respectively opened on the front cover and the rear cover.

[0014] Based on the above, in order to facilitate installation, the outer end of the front end cover and the outer end of the rear end cover are respectively extended out of the cylinder barrel.

[0015] The utility model has substantial features and progress compared with the prior art. Specifically, the utility model provides a hydraulic cylinder with an end cover anti-retraction function, wherein the front end cover is connected to the internal thread of the cylinder barrel at the front end of the cylinder barrel through a thread, and the front end cover is connected to the flange through a bolt. The rear end cover is connected to the internal thread of the other end of the cylinder barrel through a thread, and the rear end cover is connected to another flange through another set of bolts. The inner rings of the two flanges are respectively provided with flange internal threads, and the two flanges are respectively connected to the external threads at both ends of the cylinder barrel through the flange internal threads.

[0016] That is, the front cover and the rear cover are respectively threadedly connected to the inside of the cylinder, and the two flanges are threadedly connected to the outside of the cylinder. The front cover and the rear cover are respectively fixed to the flanges by bolts.

[0017] Among them, the pitch of the external thread at both ends of the cylinder is different from the pitch of the internal thread of the cylinder, which causes the pitch of the internal thread of the flange to be different from the pitch of the external thread of the front cover and the external thread of the rear cover. Therefore, the self-locking function can be achieved. Before the bolts are removed, the front cover and the rear cover cannot rotate relative to the cylinder, so that the front cover and the rear cover have the functions of preventing retreat and loosening. The structure of the hydraulic cylinder itself is used to prevent the hydraulic cylinder end cover from loosening and retreating due to vibration.

[0018] Furthermore, since the front cover and the rear cover are both threadedly connected to the cylinder barrel, and the flange is also threadedly connected to the cylinder barrel, the cylinder barrel will not be damaged during disassembly, and the requirements for multiple disassembly and assembly can be met. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The utility model is a schematic diagram of the overall cross-sectional structure of a hydraulic cylinder with an end cover anti-retraction function.

[0020] Figure 2 The utility model is a schematic diagram of the cross-sectional structure of the front end cover of the hydraulic cylinder with the end cover anti-retraction function.

[0021] Figure 3 The utility model is a schematic diagram of the cross-sectional structure of a cylinder barrel in a hydraulic cylinder with an end cover anti-retraction function.

[0022] Figure 4 The utility model is a schematic diagram of the cross-sectional structure of the rear end cover of the hydraulic cylinder with the end cover anti-retraction function.

[0023] Figure 5 The utility model is a schematic diagram of the flange structure in a hydraulic cylinder with an end cover anti-retraction function.

[0024] In the figure: 1. cylinder barrel; 2. external thread of cylinder barrel; 3. front end cover; 4. piston rod; 5. bolt; 6. piston; 7. flange; 8. rear end cover; 9. internal thread of cylinder barrel; 10. first fluid hole; 11. sealing groove; 12. bolt hole; 13. external thread of front end cover; 14. sealing surface of front end cover; 15. sealing ring groove; 16. second fluid hole; 17. external thread of rear end cover; 18. sealing surface of rear end cover; 19. internal thread of flange; 20. threaded hole. DETAILED DESCRIPTION

[0025] The technical solution of the utility model is further described in detail below through specific implementation methods.

[0026] Example 1

[0027] This embodiment provides a hydraulic cylinder with an end cover anti-retraction function, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, it includes a cylinder 1, a front cover 3, a rear cover 8 and a pair of flanges 7. The front cover 3 is threadedly connected to the inner wall of the front end of the cylinder 1. The rear cover 8 is threadedly connected to the inner wall of the rear end of the cylinder 1. The pair of flanges 7 are respectively threadedly connected to the two ends of the outer wall of the cylinder 1; the front cover 3 and the rear cover 8 are respectively connected to the flanges 7 at their respective ends by bolts 5.

[0028] The cylinder barrel 1 , the front end cover 3 , the rear end cover 8 and the pair of flanges 7 form a self-locking mechanism.

[0029] In this embodiment, both ends of the outer wall of the cylinder 1 are provided with cylinder external threads 2, and both ends of the inner wall of the cylinder are provided with cylinder internal threads 9. The pitch value of the cylinder external threads 2 is different from the pitch value of the cylinder internal threads 9.

[0030] Specifically, in this embodiment, the pitch values ​​of the cylinder external threads 2 at the two ends of the cylinder 1 are the same. The pitch values ​​of the cylinder internal threads 9 at the two ends of the cylinder are the same.

[0031] The inner end of the front end cover 3 is provided with a front end cover external thread 13. The inner end of the rear end cover 8 is provided with a rear end cover external thread 17. The pitch value of the front end cover external thread 13 is the same as the pitch value of the rear end cover external thread 17. The interior of the front end cover 3 is provided with a sealing groove 11.

[0032] like Figure 5 As shown, the flange 7 is provided with a plurality of threaded holes 20 in a circular array, and the front cover 3 and the rear cover 8 are respectively provided with a plurality of bolt holes 12. The bolt holes 12 are provided correspondingly to the threaded holes 20.

[0033] like Figure 2 and Figure 4 As shown, the inner end of the front cover 3 is provided with a front cover sealing surface 14, and the inner end of the rear cover 8 is provided with a rear cover sealing surface 18. Sealing rings are respectively sleeved on the front cover sealing surface 14 and the rear cover sealing surface 18. Sealing ring grooves 15 are respectively opened on the inner side wall of the cylinder barrel 1 corresponding to the sealing rings.

[0034] like Figure 1 As shown, a piston rod 4 is also slidably arranged in the cylinder 1, and a piston 6 is installed at the bottom end of the piston rod 4. The top end of the piston rod 4 extends out of the front end cover 3, and seals are respectively arranged between the piston rod 4 and the front end cover 3 and on the piston 6. Liquid holes are respectively opened on the front end cover 3 and the rear end cover 8. For the convenience of distinction, the two liquid holes are respectively recorded as the first liquid hole 10 and the second liquid hole 16. The outer ends of the front end cover 3 and the outer ends of the rear end cover 8 are respectively extended out of the cylinder 1.

[0035] Example 2

[0036] This embodiment provides a hydraulic cylinder with an end cover anti-retraction function. The main difference from Embodiment 1 is that in this embodiment: the pitch values ​​of the cylinder external threads at both ends of the cylinder are different, and the pitch values ​​of the flange internal threads 19 on a pair of flanges are different.

[0037] Example 3

[0038] This embodiment provides a hydraulic cylinder with an end cover anti-retraction function, which is mainly different from Embodiment 1 in that: in this embodiment, the pitch values ​​of the internal threads of the cylinder barrel at both ends of the cylinder barrel are different. The pitch value of the external threads of the front end cover is different from the pitch value of the external threads of the rear end cover.

[0039] Specifically, in the hydraulic cylinder provided in Example 1 of the utility model, the front end cover is connected to the cylinder barrel by a thread, and the pitch is n1, and the front end cover is connected to one of the flanges by one set of bolts. The rear end cover is connected to the inner thread of the cylinder barrel at the other end by a thread, and the pitch is also n1, and the rear end cover is connected to the other flange by another set of bolts. Among them, the inner rings of the two flanges are provided with flange internal threads. The two flanges are connected to the outer threads of the cylinder barrel at both ends of the cylinder barrel by threads, and the pitch is n2, and n1 is not equal to n2.

[0040] When there is a large vibration in the operation of an ordinary hydraulic cylinder, the connecting threads in the oil cylinder may become loose when the screwing torque is insufficient, and even the front cover and the rear cover may be withdrawn. However, due to the hydraulic cylinder provided in this embodiment, the two pitches are designed to be different values, and the front cover and the rear cover are connected to the flange as a whole by bolts, so that the front cover and the rear cover cannot rotate relative to the cylinder barrel, that is, the anti-retraction function of the front cover and the rear cover is realized.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the utility model can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the utility model, which should be included in the scope of the technical solution for protection of the utility model.

Claims

1. A hydraulic cylinder with an end cover anti-retraction function, comprising a cylinder barrel, a front end cover, a rear end cover and a pair of flanges, characterized in that: The front end cover is connected to the inner wall of the front end of the cylinder through threads, the rear end cover is connected to the inner wall of the rear end of the cylinder through threads, and a pair of flanges are respectively connected to the two ends of the outer wall of the cylinder through threads; the front end cover and the rear end cover are respectively connected to one of the flanges with bolts; The cylinder barrel, the front end cover, the rear end cover and a pair of flanges form a self-locking mechanism.

2. The hydraulic cylinder with end cover anti-retraction function according to claim 1, characterized in that: The two ends of the outer wall of the cylinder are respectively provided with cylinder external threads, and the two ends of the inner wall of the cylinder are respectively provided with cylinder internal threads, and the pitch value of the cylinder external threads is different from the pitch value of the cylinder internal threads.

3. The hydraulic cylinder with end cover anti-retraction function according to claim 2, characterized in that: The pitch values ​​of the external threads of the cylinder barrel at both ends of the cylinder barrel are the same.

4. The hydraulic cylinder with end cover anti-retraction function according to claim 2, characterized in that: The pitch values ​​of the internal threads of the cylinder barrel at the two ends of the cylinder barrel are the same.

5. The hydraulic cylinder with end cover anti-retraction function according to claim 3 or 4, characterized in that: The inner end of the front end cover is provided with a front end cover external thread, and the inner end of the rear end cover is provided with a rear end cover external thread. The pitch value of the front end cover external thread is the same as the pitch value of the rear end cover external thread.

6. The hydraulic cylinder with end cover anti-retraction function according to claim 5, characterized in that: The flange is provided with a plurality of threaded holes in a circular array, and the front end cover and the rear end cover are respectively provided with a plurality of bolt holes, and the bolt holes are provided correspondingly to the threaded holes.

7. The hydraulic cylinder with end cover anti-retraction function according to claim 6, characterized in that: The inner end of the front end cover is provided with a front end cover sealing surface, and the inner end of the rear end cover is provided with a rear end cover sealing surface. The front end cover sealing surface and the rear end cover sealing surface are respectively sleeved with sealing rings, and sealing ring grooves are respectively opened on the inner side wall of the cylinder corresponding to the sealing rings.

8. The hydraulic cylinder with end cover anti-retraction function according to claim 7, characterized in that: A piston rod is also slidably arranged in the cylinder barrel, a piston is installed at the bottom end of the piston rod, the top end of the piston rod extends out of the front end cover, and sealing members are respectively arranged between the piston rod and the front end cover and on the piston.

9. The hydraulic cylinder with end cover anti-retraction function according to claim 8, characterized in that: The front end cover and the rear end cover are respectively provided with liquid holes.

10. The hydraulic cylinder with end cover anti-retraction function according to claim 9, characterized in that: The outer ends of the front end cover and the rear end cover are respectively extended out of the cylinder barrel.

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